Hi - During the qualifying/race, you can:
Walk on the inside of the circuit from the Karting Nord campsite through to Tetre Rouge, although once past Karting nord, you can see nothing until you spit out of the other side of the pit village, and then you can walk up to Tetre Rouge with a few minor diversions.
Walk on the inside of the circuit from Masion Blanche all the way (including the start/finish straight opposite the pits) up to just short of Tetre Rouge corner, where there is a pedestrian tunnel to get onto the inside of the circuit.
Take your pick, but we normally walk up one side and back down the other. Porshce curves is a separate spectator area in its own right, but is walkable from the Karting Nord or Maison Blanche. Arnage and Mulsanne are separate
spectator areas best accessed by vehicle.
Enjoy and take comfortable walking shoes!